World Travel City Photography

One characteristic that can be used to distinguish a small city from a large town is organized government. A town accomplishes common goals through informal agreements between neighbors or the leadership of a chief. A city has professional administrators, regulations, and some form of taxation (food and other necessities or means to trade for them) to feed the government workers. The governments may be based on heredity, religion, military power, work projects (such as canal building), food distribution, land ownership, agriculture, commerce, manufacturing, finance, or a combination of those. Societies that live in cities are often called civilizations.
• Ancient times
Early cities developed in a number of regions of the ancient world. Mesopotamia can claim the earliest cities, particularly Eridu, Uruk, and Ur. After Mesopotamia, this culture arose in Syria and Anatolia, as shown by the city of Çatalhöyük (7500-5700BC). It is the largest Neolithic site found to date. Although it has sometimes been claimed that ancient Egypt lacked urbanism, several types of urban settlements were found in ancient times.
The Indus Valley Civilization and ancient China are two other areas with major indigenous urban traditions. Among the early Old World cities, Mohenjo-daro of the Indus Valley Civilization in present-day Pakistan, existing from about 2600 BC to 1900 BC, was one of the largest, with an estimated population of 40,000 or more. Mohenjo-daro and Harappa, the large Indus capitals, were among the first cities to use grid plans, drainage, flush toilets, urban sanitation systems, and sewage systems. At a somewhat later time, a distinctive urban tradition developed in the Khmer region of Cambodia, where Angkor grew into one of the largest cities (in area) of the world.